Which choice shows (40+10)+30 correctly rewritten using the associative property and then correctly simplified?

40 + (10 + 30) = 40 + 40 = 80

40 + 30 + 10 = 70 + 10 = 80

40 + (10 +30) = 50 + 30 =80

(10 +40) + 30 = 50 + 30 =80